Device for the development of light sensitive materials



y v16, 1 A. SCHADE El AL 0 DEVICE FOR THE DEVELOPMENT OF LIGHT SENSITIVE MATERIALS,

Filed June 24, 1937 2 Sheets-Sheefl Arthur Schade |NVENTOR$ Josef Horn ms ATTORNEYS July '16, 1940; A. SCHADE El Al.

DEVICE FOR THE. DEVELOPMENT OF LIGHT SENSiTIvE MATERIALS 2 Sheets-Sheet 2 Filed June 24, 1937 INVENTORS I THEIR ATTORNEYS I Arthur \Sc/Lade Josef Horn all/[17171]], II

Patented July 16, 1940 UNITED STATES DEVICE FOR THE DEVELOPMENT OF LIGHT SENSITIVE MATERIALS Arthur Schade and Josef Horn, Wiesbaden- Biebricli, Germany, asslgnors to Kalle & Co. Aktiengesellschaft, Wiesbaden-Biebrich, Germany Application June 24, 1937, Serial No. 150,108 In Germany June 26, 1936 3 Claims. (CI. 95-90) The present invention relates to a device for the development of light-sensitive materials, particularly photographic prints by means of ilowing gases, such as, for example, ammonia. The

5 device is especially suitable for the development of prints, or the like, of small sizes and is intend- -ed particularly for such use in omces.

One object of the present invention is a developing device in which a large number of prints can simultaneously be developed. Another object of the invention is a developing device which makes possible the insertion of the prints in an unrolled condition, in the developing chamber, in such a manner that they stand on their edges and that. the developing gas can sweep along their surfaces. In this manner, a

particularly rapid and complete development of v A further object of the invention is a develop- I ing device in which the developing chamber and 25 the inlet and outlet conduits for the developing gas and the scavenging air are constructed and arranged in a particular manner. An object of the invention is, for example, a developing chamber which is in the form-of a quadrilateral rec- 30 tangular prism (quadrone) The one edge of the prism is thereby made of such a length as only amounts to a fraction, for example a tenth, of the length of the other two edges. For the development ofmost of the sizes of prints coming 85 into consideration in ofilces a chamber having dimensions of 30 cm. x 40 cm. x 4 cm. is, for example, suitable. The said developing chamber is to be arranged in the developing apparatus in such manner that the four short edges are hori- 40 zontally or approximately horizontally located.

One of the narrow sides of the chamber is preferably located in a horizontal plane. chambers of this kind small piles of prints can be introduced in such manner thatthe indi- 45 vidual prints stand on their edges. Naturally the chamber does not need to be accurately of prismatic form, but it must approximately correspond to the form of a prism. The inlet and outlet conduits for the developing gas are preferably 59 arranged at or in proximity to two oppositely located narrow sides of the chamber so that the direction of the stream of gas runs parallel to the siu'faces of the individual prints of the inserted pile of prints and vertically to the short 55 edge of the developing chamber. The gases are preferably blown through the chamber in vertical or inclined direction from the lower part of the chamber to the upper part. The developing chamber is adapted to be closed in a gas-tight so manner by means of a door, flap or the like.

Into 7 Another object of the invention is a separate chamber in which the developing gas is produced. A further object of the invention is an airing or degassing device provided with an air inlet and an air outlet conduit. Another object I of the invention is a suitable valve system, which is arranged in such a manner that the developing chamber can be connected as desired through a ventilator with the gas container in order to establish a gas circuit or with the degassing del glee. The valve usedis preferably of the rotary 'A further object of the invention is a chamber filled with water which is preferably inserted in the inlet path of the air serving for the scaveng- 15 ing of the developing chamber. In the said water chamber the scavenging .air becomes charged with water vapor. Furthermore, it is advantageous to provide a heating device for heating the scavenging air. The discharge conduit for the scavenging air may be put into connection with the outer air in known manner by means of a long pipe, in order to prevent the occurrence of a noxious odor in the work-room through the gases which are drawn off.

Another object of the invention are means for closing the door of the developing chamber. It is preferable to. provide in combination with these means a bolt, the removal of which during the developing is prevented owing to its being coupled in a suitable manner with the valve system. 7

A preferred constructional form of a device according to the invention is illustrated by way of example in Figs. 1 and 2 of the accompanying drawings. Fig. 2 shows a longitudinal section along the line 3 :c of Fig. l and Fig. 1 shows a longitudinal section along the line 11 y of Fig. 2. Fig. 3 shows the path of the gas during the developing operation and Figure 4 shows the 40 path of the scavenging air during the ventilating operation. The device consists of a housing which is made preferably by casting, of a material resistant to ammonia. In the housing the gas chamber I, the water chamber 2 and the developing chamber 3 are arranged. The wall ll separates the water chamber from the air discharge pipe. Besides this housings for a ventilator 4,

a rotary valve 5 and also various connecting conduits are provided. These individual parts are preferably provided at the outset in the casting.

The gas chamber l is supplied with the aqueous solution of ammonia by means of a conduit pipe 6 which can be closed by means of a stopper. The waste solution can be drawn ofl by means of the draining pipe .1. For accelerating the evaporation heating means may be provided.

The water chamber 2 is either itself filled with water or is equipped with a dish filled with water. In order to increase the evaporation surm face aporous stone having a surface as large as possible may be placed in the dish or a filter serving for heating the scavenging air sucked in through the slit 9. I

The developing chamber proper 3 is made fairly narrow and corresponds in its height and depth to the sizes to be developed. The developing chamber is adapted to be closed by means of a door I0 provided with rubber packing. This door may be securedby means of a separate bolt ll during the development. The said bolt is connected with the lever l2 serving to make use of the rotary valve 5 in such a manner that it is not possible to open the door during the developing process.

The rotary valve 5 consists of two parts which arecompletely separated from one another by means of a solid separating wall. The one part i3, in the corresponding position of the rotary valve, leads the gas from the ventilator pressure pipe to the ammonia chamber I, while the other part Min the same position allows the gas to pass from the ammonia chamber into the developing chamber 3 (development). In another position ofthe rotary valve the one side of the latter l3 allows the scavenging air to flow from the ventilator pressure pipe to the air discharge pipe I6, while the other side of the rotary valve l4 conducts the scavenging air from the water chamber 2 to the developing chamber 3 (scavenging). On the one side of the rotary valve a lever or hand wheel l2 for moving it is mounted.

The mode of operation of the device is as follows: The prints to be developed are preferably placed in a quantity of 20-30 sheets in a case 15 which is constructed of rods or perforated sheet metal or wire netting. The breadth of the case is a multiple of the thickness of the sheet pile to be developed, so that the sheets to be developed rest very loosely in the case.

The case is then inserted'in the developing chamber in such a manner that the developing gases or the scavenging air respectively can easily sweep through between the sheets. After the case with the sheets has been inserted in the developing chamber, the door it! is closed. Now, the ventilator 4 is set in action and the rotary valve is brought into such position that a circuitous flow of the developing gas through the developing chamber is caused. When the development of the sheets is complete the rotary valve is brought into such position that a stream of air flows through the developing chamber. As a result of this, the residual ammonia gas is blown out of the developing chamber. When the prints have been sufficiently freed from the developing gas, the door is opened and the case with the sheets which have been developed and freed from the developing gas is removed from the developing chamber.

In Figs. 1 and 2 of the drawings, the rotary valve is in the position of development. [8 is a pile of prints.

We claim: i

1. A device for the development of photographic prints by the aid of gaseous developing means comprising a developing chamber approximately in the form of a quadrilateral rectangular prism,

;'in combination with the said developing cham- ;'ber, a gas container, a gas inlet conduit and a paper may be hung therein. 8 is a heating means gas outlet conduit in combination with the said gas container, two valves in the form of threeway cocks connecting the said conduits of the developing chamber with the saidconduits of the gas container, the third way of'eachof the valves being connected with the open air and a ventilating system disposed between one of the valves and the corresponding gas conduit of the developing chamber, the inlet and outlet conduits of I .to only a fraction of the length of the two other edges, the said chamber being so arranged that the short edge is located horizontally, a gas inlet conduit and a gas outlet conduit in combination with the saiddeveloping chamber, a gas container, 2, gas inlet conduit and a gas outlet conduit in combination with the said gas con tainer, two valves in the form of three-way cocks operated on the same rod connecting the said conduits of the developing chamber with the said conduits of the gas container, the third way of each of the valves being connected with the open air and a ventilating system disposed between one of the valves and the corresponding gas conduit of the developing chamber, the inlet and outlet conduits of the developing chamber being so arranged that the developing gases, when the ventilating system is set in action are blown through the developing chamber perpendicularly to the short edge of the latter.

3. A device of the mentioned type comprising a developing chamber in the form of a quadrilateral rectangular prism, the one edge of which is of a. length which amounts to only a fraction of the length of the two other edges, the said chamber being so arranged, that one of the narrow sides of the said chamber is located in a horizontal plane, a gas inlet conduit and a gas outlet conduit in combination with the said developing chamber, a gas inlet conduit and a gas outlet conduit in combination with the said gas container, a rotary valve in the form of a double three-Way cock connecting the said conduits of the developing chamber with the said conduits of the gas container, the third Way of each of the cocks being connected with the open air, a ventilating system disposed between one of the cooks and the corresponding opening of the developing chamber, the inlet and outlet conduits of the developing chamber being so arranged that the developing gases can be blown through the developing chamber in a direction parallel to the largest side of the developing chamber, a chamber filled with water and also a heating arrangement provided in the conduit serving for the introduction of the scavenging air, a door in the said developing chamber and a bolt in combination with the said rotary valve serving for preventing the opening of the said door of the developing chamber during the development.

ARTHUR scHAnE. JOSEF HORN. 

